Tread-cutting machine for tire molds



Oct. 5 1926. 1,601,999

J. F. CULLEN TREAD CUTTING MACHINE FOR TIRE MOLDS Filec} A fil 13, .925 e Shets-Sheet' 1 6 Sheets-Sheet 2 J. F. CULLEN Filed April 13 TREAD CUTTING MACHINE FOR TIRE MOLDS Oct. 5,1926. 1,601,999 I J. F. CULLEN TREAD CUTTING MACHINE FOR TIRE HOLDS Filed April 13, .925 e Sheets-Sheet 5 V abtozweq 5 6 Sheets-Sheet 5 Filed April 15, 1925 MEa J. F. CULL EN TBEAD CUTTING MACHINE FOR TIRE HOLDS Filed April 13.1925 6 Sheets-Sheet e will do the work required of it as well as and in some respectsbetter than the highest Patented Oct. 5j 192i6.

JULIEN r; -CULLEN, or ron'rnann, onneon;

'rnnan-cu'rrnv'e MACHINE ron TIRE moms,

Application filed A rn 1a, 1925. Serial in. 22,903.

My invention relates to'machines for cutting non-skid groovesor patterns in metallic mold members for molding rubber tires.

Machines for cutting tire molds have'been regarded hithertoas too expensive, both in respect to cost of production and, largely because of their functional limitations, in"respect to their cost of operation. Besides,

' they have been uncertain in results obtained unless operated with greatest care and oftendespite the exercise thereof.

B m invention I have reduced a comy a paratively simple and cheap machine, which priced machine; which may be operated at a minimum of expense; wlnch produces,

- with certainty and equality of distribution,

any desired pattern of cut; and which is adapted, by mere change of its supporting base, to be applied to a mold member of any usual or practicable diameter preferred.

- 'ing-to the sheet.

The further scope of my invention will be set forth in the following specification.

Vhat constitutes -my invention will be hereinafter described in detail and succinctly defined in the appended claims.

In the accompanying drawings, in which my invention is illustrated in its present preferred form of embodiment,

Figure I is a top plan view of my-machine, which is, except motor, substantiallycomplete, and is applied in operative relationship to a tire mold member, which is shown as broken away at its opposite sides for accommodation of the scale of the draw- Figure II is a side elevation of the subject matter of Figure I, showing the base support of the machine, the tire mold member to which it is applied, and the dividing plate, respectively, in diametrical section..

Figure III is a horizontal section on the line III-III of Figure II, looking in the direction indicated by the darts thereon, portions of the latter figure being omitted. Figure IV is a detail side elevation, artly in section, of the cutting-tool head su stantially at the bottom of its cut, and parts of its operating mechanism, thesame being shown as broken away from the rest of the machine whereof parts are illustrated.

Figure V is a companion view of Figure IV taken at right angles thereto, and in doing of its work.

end elevation of a portion of Figure II,

looking from left to ri ht, some partsbeing' in section, and some roken away.

Figure VI is a view corresponding to Figure IV, but showing the cutting-tool at the'beginning of its cut, instead of ad vanced into it as shown in the last named figure.

Figure VII is an elevation partly sec:-

tion of the subject matter of Flgure VI, and a at right angles thereto.

Figure VIII is a side elevation .ot a portion of thesubject matter of Figure III taken at right angles to the latter plane of new.

a stretch of a tread-cut made b guidance 7 of the cutting-tool effected by t e. form of templet shown in Figure IX.

Referring to. the numerals on the drawings, Iin'dicates a tire mold member'or one .half of a split mold, which represents" the so" object upon which my cutting machine is designed and adapted to operate in .the'

In Figure 'I of the drawings, the, niold member 1 is shown as ablank or an uncut.

one ready for cutting. The member 1 may be one half of the usual split type mold, and provided with an internal preferably annular flange 2. Within the inner circumference of the mold member 1, I provide a base support 3, which is secured snu 1y, firmly, and accurately to the surroun mg mold member 1, so that the parts 1 and Q are, with substantial exactitude, disposed c0- axially one towards the other. To that end,

the flange 2 may be provided with a depression into which snugly fits an annular footpiece 4, which is secured to the flange 2 by any suitable means, for example a ring of ta bolts 5.

ase supports 3 are made in practice of different eights and different diameters and are so'adapted interchangeably to. fit

within different sizes of molds, according to any preferred standardization of size which may be adopted therefor in tire manufachim; but base supports of all sizes are, through their interc ange, adapted equally Figure IXisa top plan -view of the temi to accommodate and operatively to support one and the same cutting machine.

Interchange of base. supports}, therefore, affords, without any other provision, means for adapting my machine to the cutting of treads for all sizes of tire molds. This, it should benoted, is an important and valuable featureof myinvention. I

The interchange of base supports 3, as aforesaid, is provided for simply by making *each of such supports, irrespective of its size, in the form of a hub socket having sufiicient weight and extent to furnish stable support to a post 7 whose reduced end 8 (Figure II) is fitted into the bore of said member 3.

A feather 9, or other mechanical device, may be employed at will for irrevolubly uniting theparts 3 and 8, they being also united preferably by a set screw as shown in Figure II. o

The proper function of my machine is to cut grooves 10, of which one is shown, for example, in Figures II and VI of the drawings, in the tread-molding face 11 of the mold 1, said grooves being shaped and relatively disposed according to any predetermined pattern, such as that indicated, 'for example only, by the numeral 12 in Figure Xpf the drawings.

The cutting operation referred to in the last paragraph is performed by the direct instrumentality of acutting-tool 15, or for brevity a cutter, which, in its step by step cutting progress, makes an-operative sweep around the entire circumference of the mold member-1. j

In this connection the reason for mounting the post 7 in firmly fixed, coaxial relationship to the mold member 1 now begins to appear, since it is obvious that if the axis of the post 7 is made constantly to coincide with the central axis of the mold 1, it will be suflicient, in order to accomplish the end in view, properly to mount the cutter 15 on a member which will revolve (oaxially about the said axis.

It will also be apparent that by so mounting the cutter it maybe made to move about said axis in a circle of any desired diameter,

' thereby, in so far and without radical change varied adapting the machine for cutting ofthe machine, adapting, asalready stated, the same cutting-tool to functionate upon mold members of various sizes regardless. of what the diameter of each, within the, working limits of the machine, ma be. The height, also, of the post 7-shou d be treads on molds of different sizes, but this ,may be accomplished b shipping the post in a base, support 3 o a di erent height v such as may selected for the occasion.

With the foregoing suggestion of the -rea-' son for so doing it is specified that the cut'- ter 15 is operat vely. mounted upon astifi' horizontal beam 16 which projects radially from a rotatable bearing member or sleeve 17 with which it is preferably made' inte-.

gral. Said sleeve is supported by the up- 1' per face of the base support 3,.and is revolubly but snugly fitted, to the post 7 in the manner shown, for example, in F i ire II.

The cutter l5-is carried immediate y by an arbor 18 that is, in'suitable bearings indicated b 1 the numerals 19 and 19,-- journaled on a rocking carriage 20', that'is movable upon a pivotal supporter" 21 which is, in

set, provided for it on the beam 16, so as to impart through it oscillatory movement to the arbor 18 in the vertical plane with which the longitudinal axis of said arbor drawing, is provided with a peripherical ofiset ledge 23, whose width measures the depth of the grooves 10, and into which in operation the teeth of the cutter bites.

If occasion require, the cutter, however, may be made to bore its own way'into the metal of the mold as well as to cut, or besides cutting, laterally into it. This is of course an ordinary incident in the making of cutting tools to which it is deemed to be necessary only, to allude in this connection, in order to indicate that such variation of tool is contemplated as vcoming within the scope of my invention, it being noted that the cutter is provided with an ordinary set-nut 251 by aid ofwhich the cutter may be fixed in place or removed from its arbor as often as occasion for its renewal or replacement may occur.-

The cutting-tool-arbor .18 is,-. as. by a flanged belt-pulley 25, revolubly fixed to" its end opposite to that to which'the cutter r 15 is fixed, driven by anysuitable means such as will permit both the sleeve 17 and the beam 16-to revolve freely about the post 7 without any interfering with the operativeness of connection between the pulley 25 and its driver. A simple and therefore preferred form of such driving mechanism is shown, for example, in Figure VIII inwhich an electric'motor 27 whose rotative shaft is operatively'connected by a belt 28 with I the pulley 25, the motor bein mounted upona platform or sup orting ame-3O WhlCh is secured to the sleeve 17"and'projects Ion-'- gitudinally. therefrom substantially at right angles horizontally the longitudinal axis 7 of the arbor 1'8; Brace rods 31, for example, fastened, respectively', at one end to the'said'sleeve and at the other end totheframe 30, 'serve to sustain the weight of, said framean d of any motor it may be required to carry.-

Reverting now, to consideration of the mc i s rr eg 20, 3 is e fi 'fu explanationof 'it' that its function is tocontrol and direct, to the extent of its vertical swingin movement, thelateral cutting operation f the cutter 15, whose connection with'it has already been specified. Such swinging movement ispositively imparted to the carriage 20 upon its pivotal supporter 21 by aid of any suitable mechanism which may be relied' upon to accomplish the object desired. For the purpose, 1 prefer, to construct the carriage 20 in the form and with the effect of a segmental gear, as isv well shown in FiguresIV and VI, and to provide it with an offset "segmental rack v 33 having worm teeth 34. The offset of the rack'33 is provided in order to accommodate the "presence of a' sector-plate 35 having an overhung flange 37 with which a lip 38, provided on the segmental edge of the citrriage 20, slidingly engages, with the effect of steadying, to sibstantial rigidity, the oscillatory movement of the carriage. The

. plate 35 is, as by countersunk screws 39,

fastened to the face of the traveler 40, which moves, back and forth on the beam 16,

and on which the carriage 20 is securely mounted. The preferred means for slidably attaching the traveler to the beam 16, are flanges 41 each having a height substantially equal to the thickness of the. beam.

- The flanges 41 engage the opposite sides of the beam 16, and are heldto it by overhang- .ing plates 43, which are respectiyely bolted to a longitudinally extending, preferably integral strip 44 -upon the beam 16. The

precise construction of merely ordinary mechanical elements is, of course, offered, in

the present instance as in all instances; preferentially only and by way. of example.

The said strip 44 affords" a suitable. and) conveniently disposed support for a bracket 45- (Figure V), that is bolted to it so as .to

present a shelf {16 for. the firm support of a collar-bearing 48 in which rotates a longin tudinally fixed shaft 49.

The shaft 49 is provided with a handle 50 by whichit may be rotated at will in either direction. Its end opp'ositejthe handle 50 is threaded into a lug52 (see Fig. V) which is preferably bolted'to and projects,

' preferably downwardly, from the bottom of a frame 53 which is preferably bifurcated or 'U-shaped. The legs 54 and 55, respectively, of the frame 53, straddle and are secured to a common plate 57 which unites .them and which collars the post 7 upon 'whichitis free to rotate above the sleeve 17 (compare Figures I..and II) under impulse. in either direction imparted to it by rotation of theshaft 4:9. h X

- Atem let- 58Jspans, as shown in Figure I, the longitudinally disposed opening defined p by the leigs'54 and 55 in the U-shaped frame; 1ich itis secured s by. bolts; 60.

53, to w r On the top of the templet 5 is adjustably chine produces.

mounted an auxiliary templet '59 which while the machine is in operation is operf atively fixed to the templet as by fastening members 61 and 62. The member 62 works in atransverse slot. 63 in the member 59 (see Figure I) for the purpose hereinafter explained.

The templet-is penetrated by an opening that is bounded by .a wall 63 the shape of whose periphery determines the pattern which, through the guidance imparted by it to the cutter 15, theopera-tion of the ma- The shape or configuration of the wall- 63 may be considerably varied to an indefinite. extent. Such shape of it as clearly shown in .Figures I and-IX will,- as a result'of operation of the machine in the proper man ner and-upon a proper object, produce a.

tread-cut if. the pattern illustrated in Figure X, which is no more than a sample pattern and'is so intended to be taken.

The manner in which the templet 5 8 and p the auxiliary tcmplet 59 functionate remains to be xplaincd. For that purpose it is necessary to revert to description of the carriage 20 which has hitherto only specifiedthat the I segmental rack 33 thereofis provided with worm teeth 34. Extendingthat description, 65 indicates a worm'which intermeshes" with the teeth 34, as shown, for exam 1e in Figures IV and VI,- and which is. xed longitudinally upon a rotative shaft 66 being disposed between two stop lugs 67 and 68, which servealso as journals to one end of said shaft as is well shown in Figure III. Near its other end, the shaft 66 is journaled,

as shown in Figure III, 'in a third'corresponding lug 69. The three journal lugs. 67, 68, and 69, project from an elongated stifl supporting bar 71, which,'at the end next to which the lugs 67 and 68 are located,

is secured to the traveller 40, as by bolts 72.

;'1he shaft 66, where it extends beyond the lug 69 is provided with a handle 73, by-

which it may be rotated in either direction,

20 is firmly secured.

entire periphery, with the result, in the instance herein illustrated and described,- of causing the cutter 15 to cut into'the inner. face ll'of the mold member 1, and to form lts 75 a. base plate 76 from which therein the' pattern whicli'is illustrated and is "functioning. For accomplishing that purpose, as well as for imparting step by step to the frame 53 rotative movement about the post 7, I prefer to employ a divid- Qing plate 80 (compare Figures I, II, and VIII).

The dividing plate 80 is so denominated because its proper function is to divide into v component parts the circle of rotation of the 7 frame 53. Those parts should be e ual, to

' said the extent of substantial exaetitu e, because the patern 1 2, to effect whose production the division of the circle ofv rotation of the frame 53 is provided, is, in its completeness, of annular form, and is made. up of repetitions of the same design constituting what may be called a sub-pattern, each of which is juxtaposed to its next neighbor on either side to make up such an entire series thereof as will complete the pattern 12.

It is obvious that in order to produeea symmetrically perfect pattern 12 each of the sub-patterns composing it must so exactly fill a definite equal space as to insure that therewill be nowhere in the complete pattern 12 any break between the sub-patterns or any overlapping of them one upon another. This result is accomplished unerringlyand to substantial perfection by my dividing plate 80. Moreover, the use of plate makes it possible, at will, 0- curate y to verify and correct, if need e, every cutting operation of the cutter 15 after it has been performed or has beenintended to be performed, as will be clearly explained in the following description.

To effect the purpose just indicated, the plate 80 is provided nan its outer periphery with a ring of apertures 81. each being spaced equidistantly from its next neighbor.

The plate 80 is feathered, as indicated at .83, 'or otherwise irr'evolublysecured to the post 7, above a collar .84 which surmounts and is aflixed to the frame 53.

The plate 80 is provided with a collar 85 for the purpose of conveniently fastening the plate to the post 7 as by aid of a set screw 86.

A stud-post 87, upstanding from vthe I frame 53 and secured to it, as by aid of a foot-piece 88'and1tap bolts 89, is provided in its top with a vertical peg-socket 90.

The axis of-the socket 90 eoincideswith that of each aperture 81, at such time as they are successively bi ought into alignment by rotation of the frame 53. A removably adjustable pegv 91 serves by its presence when it is inserted through any one of the aper t res 81 into the socket 90, to fix the relation 0} the frame 53 to the plate 80. -Readjustment of the'peg from one aperture 81' to another imparts in regular orderof advancement, a step by step relative disposition of the rotative frame 53 in respect to the dividingplate 80 which is, fixed to the post-7 on which said frame rotates.

In addition to. what is already specified, I prefer to provide mechanism for increasing or diminishing, the effective length of the arbor 18. To that .end there may be 'emloyed the means, for example, illustrated m'F'igures IV to VII,.inclusive, wherein the arbor 18 is shown as revolubly fixedbut slidingly movable on the carriage 20. For that purpose a sleeve 93 which is rotatably confined at its opposite ends between collars 100 and 101 fixed to the arbor 18, is threaded through a box 94. bolted orotherwise secured to the carriage 20, so that through its rotation it may causethe arbor 18 which carries the cutter 15 -to advance or retreat slidably in its bearings 19 and 19' with the result of lengthening or shortening in effect the arbor 18. For so rotating the'sleeve' 93 a worm gear 95 may be fixed to it in intermeshing as above specified in its bearings 19 and 19 is preferably carried in the'bari ng 19' through the operative interposition between -it and said bearing of a\bushing. Said bushing preferably consists of the reduced end 103 of a coaxial integral sleeve 104 on the pulley 25. A collar 105 fixed to the reduced end 103 df the sleeve 10A serves to may be provided for its accommodation.

- Thereupon a base support3, properly selected. to suit the size of said mold-member, is bolted to it, as has been hereinbefore specified. Afterwards-the cutter 15 is operatively applied with cutting effect upon the member 1, through manipulation by the operator of "the handles 50 and 73, the dividing plate 80 being set in step by step advancement of rotation as the cutting operation proceeds.

When the pattern 12, for example, has

been completely cut, the machine has per formedthe work it is required to do, and is ready to be put to'work-on another moldmember '1' after the latter shall have been substituted for the com leted one just named. It is not indispensa y necessar for the operatorto be certain each time e inserts 1 r combination of a base adapted to be detach- 70 'thepeg 91 into an aperture 81 that said aperture is the next successive one in the series of .such apertures. It may, in fact,

be any one of'the series without disturbing, \in any wise, the work offt he machinefand therefore, if the operator should skip one or more of the apertures 81 in series, he may, upon inspection of the cut mold-memher 1, at any time rectify'any oversight in that respect which may have occurred in injuriously affecting the work put out by the machine. Moreover, the operator, after he deems a" job complete may inspect it, and

if he finds any defect or omission in it may instantly apply the cutter 15 to correct or remove the same. It remains to be explained that the auxiliary templet 59 is provided as a means for cutting certain. patterns, for example 12, whereby aslight devia'tionof movement from the templet 58 may be imparted to the roller 78 with corresponding effect upon the cut made by the cutter 15, with the result of veiliecting a clean cutting away of the metal. The use of the auxiliary templet is not necessary in the cuttin of all designs of tread patterns. WVhere 1t is found necessary or convenient to employ it, it is, by manipulat-ion of the member 62, swung in one direction or the other upon the member 61 a a pivot with the effect of affording mechanical guidance to the roller 78 for throwing it slightly out of the line'of travel which would i .cumferen tially of the irhild member, means for adjustirfg'the cutter radially of the mold and about an axis extending transversely of the axisabout which it is moved circumferentiallyv of the mold, a template controlling movement of the cutter about said' transversely extending axis, and means for actuating thev cutter in any adjusted relation.

2. ,In a machine of the kind described, the combination ofa base adapted to be detachably secured to the meld member to be cut and having a post arranged in coaxial relation to themold member, a cutter supporting arm adapt-ed to be adjusted about-the post as an'axis to vary theposition of the cltter circumferentially of the mold memb r, means supported by the post adjacent its outer end for cooperating with the cutter supporting arm to retain the arm in the dethe sequence'of cutting operations, without.

be'i-mpa-rted to it by engagementwith the sired positioncircumferentially of the mold, a rotatable cutter mounted on said arm, and means for actuating the cutter.

3. In a machineof the kinddescribed, the

ably. secured to the mold member to be cut and having a hub arranged in coaxial relation to the mold member,- a post having 'one end'fitted in said hub, an arm rotatably connected at one end to said post and extending 7B radially therefrom, a cutter carriage mount ed on said armto reciprocate longitudinally thereof, acutter supported by said carriage to rock about an axis extending transversely of'the arm, means for holding said'arm in any oneof a plur'alityof predetermined positions circumferentially of the mold memher, and means for actuating the cutter.

4. The combination with a machine as described in claim 3, of a circular mold 35 member having an internal annular flange coaxial with said member and adapted auto- Imatically to center any base support of said machine so as to constitute .the mold member an operative support for'the machine.

5. Ina machine of the kind described,- the combination of an, upright or 0st,

means for supporting said post in a ositionv coaxial with a circular mold mem. er, an arm mounted to rotate about the post, means for retaimng'said arm ma position extending in any desired radial direction from the post comprising a disk. fixed to the post and provided with a series of circumferential equally spaced apertures, aipin adapted t3 aper ures an be passed through any of sai means on the arm for'engaging the pin, a

cutter carried bysaid arm, and means for actuating the cutter.

- ,6. In a machine of the kind described,

the combination witha ba'sesupport, an arm extendingradially from and ad ustable about a post on said base, a traveller engaging said arm, means for moving the traveller longitudinally of the arm, a cutter carrier supported by and depending from the traveller, means for rocking the carrier about an axis extending transversely of the length ofthe supporting arm, a rotatable 'cutter mounted inHsaid-carrier, means for 1 rotating the fitter-,.a template on said supporting arm, and means on the carriagecontacting with the template, for the purpose 'descri ed.

7. In a machine of the kind described,

the combination with a base support, cutteroperatmg mechamsmcomprising a revoluble arm, a vertically rocking carriage on sa d arm, and a rotative cutting-tool arbor 'mounted on the carnage, of driving m'echanism for rotating the arbor, means for operatively imparting motion to the carri-age from and towards the base support in a direction radial to the vertical axis of said revoluble arm, a templet, supported above the path of travel of the'carriage, a

. guide arm .on the carriage having a free end ada ted .to follow the contour. of the ,templet, and manipulative nieans for ,causing operative engagement between said arm and teniplet with theeffect of directing the cutting operation of the cutting-tool. '8. In a machine of the kind described, the combination with a base supopo'rt, cutteroperating mechanism revolu ly mounted thereon and comprisinga vertically rockingcarriage, and a rotative cutting-tool :arbormounted on the carriage, of driving mechanism for rotating the arbor, means for operatively imparting motion to the carriage from and towards the base support in a direction radial to its vertical axis, a templet, a movable auxiliary templet, 'a guide arm on the carriage having a free end adaptedto follow the contour of the templet, and manipulative means for caus ing operative engagement between said arm and one of said templets with the efi'ect of directing the cutting operation of thecuta dividing plate fixed to the post, above the beam, means for operatively uniting the ,a traveller, means for plate to the beam for efiectin'g la, step;;by-

step adjustmentv of the beam to the post j the plane of rotation of the beam, a cutting tool arbor operatively mounted on the-beam,

means 'for directingat-will operative move- 1 ment of the arbor on the beam, and driving r 10. In a machine of the kind the combination with a post, and means for securing it in operative relationship to a member to be operated upon, of a radially disposed beam revolubly mounted thereon, v

adjus'tably position ing' the traveller longitudinally upon the beam, a roe-king carriage carried by the traveller, means for imparting vertical swinging movement to the carriage, a cutting-tool arbor opcratively and slidably' mounted. on the carriage, driving mechanism for said arbor in operative communication therewith in any position it may assume in its rotation about the post, and mechanism for imparting longitudinal 0perxative adjustment to the arbor, said mechanism consisting of a sleeve rotatably fixed to the arbor, a Worm gear fixed to the sleeve, and a manipulative" worm meshing with the worm gear. I Intestimony whereof, Ihav'e hereunto set myahand.

YJULIEN F. cULLEu. 

